JPS6040112B2 - magnetic bubble detector - Google Patents

Description

[Detailed description of the invention] The present invention relates to a detector for an ion implanted magnetic bubble device.

In conventional magnetic bubble elements, in order to transfer magnetic bubbles (hereinafter simply referred to as bubbles), permalloy pieces having a shape such as a T-bar pattern, a YY pattern, or an asymmetric Scheffron pattern are formed on magnetic garnet ( (hereinafter referred to as permalloid device). However, in a magnetic bubble element using such a permalloy transfer pattern, the bubble diameter is reduced to about lAm (microns) or less.
It is very difficult to reduce the size of the pattern due to the lithography technology and drive technology needed to form the pattern. Therefore, a continuous disk bubble device (hereinafter referred to as a CD device) has been proposed as a method of obtaining a higher density magnetic bubble device. The basic concept of bubble transfer using a contiguous disk pattern is described in A.1.P.Conference Proceedings (A.1.P.
) No. 1, page 339 (1973), as an article by Welfe et al. Furthermore, regarding the configuration of a continuous disk bubble element, IJN et al.
ctionsonNnegnetics) No. 15 No. 16
42 pages (197g King) and The Bell System Technical Journal by Nelson et al. of Bell Laboratories (m
e&11Sys m TechnicaIJourna
l) As detailed in articles such as Volume 50, Page 229 (198th King).

Conventionally, in permalloy devices, bubble detectors use the magnetoresistive effect of permalloy thin films, and in order to achieve detection with a good signal-to-noise ratio, bubbles are gradually stretched using a permalloy stretcher to detect striped magnetic domains. I was going.

After detection, the stretched striped magnetic domain can be gradually contracted into a bubble and transferred again. That is, non-destructive reading is possible. However, for CD devices, a stretcher that gradually stretches or gradually contracts the bubble over many rotating magnetic field periods has not yet been developed.

FIG. 1 is an example of a bubble detector used in a CD device. Reference number 1 is a measuring line, reference number 11 is a magnetoresistive effect detection element, reference number 12 is a stretcher conductor pattern, and reference number 21 is a rotating magnetic field. To explain the operation of the detector shown in FIG. 1, the bubble to be detected is driven by the rotating magnetic field 21 and moves on the measuring line 1 from right to left. When the bubble approaches the cusp 2, a pulse current is applied to the conductor pattern 12, and the bubble is transferred to the conductor pattern 1.
2 and detected by the magnetoresistive element 11. The striped magnetic domain stretched by the current returns to the bubble domain when the current is cut off, but it does not necessarily return to the cusp 2, and the baffle row cannot be maintained as it was. Therefore, the bubbles have to be eliminated by passing a current that is opposite to the pulse current through the conductor pattern 12 within the same period of the rotating magnetic field. That is, the CD device has the disadvantage that only destructive reading is possible. SUMMARY OF THE INVENTION An object of the present invention is to eliminate such conventional drawbacks and provide a bubble detector that can be read out non-destructively. According to the invention,
A transfer path for transferring magnetic bubbles by an in-plane rotating magnetic field is provided on a magnetic film capable of holding bubbles, and a first conductor and a second conductor are further arranged via an insulating layer, and a In the bubble detector that detects the presence or absence of bubbles using the first conductor by applying an electric current to expand and expand the bubbles, the second conductor is a pin-shaped conductor having a bent portion at the tip thereof, and A magnetic bubble detector is obtained in which a portion of the bending portion of the second conductor overlaps with the bent portion of the second conductor.

Next, the present invention will be explained in detail with reference to the drawings.

FIG. 2 is a pattern diagram showing the first embodiment of the present invention,
Magnetoresistive effect detection conductor 11 and conductor pattern 1 with bent tip
2 are arranged with an insulating layer in between, and the transfer path 1 formed by ion implantation and the conductor pattern 12 overlap at the cusp 2. Reference numeral 21 is an in-plane rotating magnetic field. When the bubble to be detected is driven by the in-plane magnetic field 21 and moves from right to left on the transfer path 1 and reaches the cusp 2, the conductor pattern 1
A pulse current is applied to the conductor pattern 2 to bend and extend the tip within the conductor pattern 12, and the result is detected by the magnetoresistive element 11.

The pattern current is maintained until the rotating magnetic field rotates and the charged wall 3 moves to the exit of the cusp 2, and then the pattern current is cut off. It interacts with 3, shrinks to the charged wall 3 part, becomes a bubble, and returns to the major line again. FIG. 3 is a pattern diagram showing a second embodiment of the present invention.

In the figure, a magnetoresistive effect detection conductor 11 and a conductor pattern 12 with a bent tip are arranged with an insulating layer interposed therebetween, and a transfer path 1 formed of a European magnetic material and the conductor pattern 12 overlap at a gap 2. . Reference numeral 21 is an in-plane rotating magnetic field. The principle of operation is the same except that the thing that attracts bubbles changes from a charge to a magnetic charge.

FIG. 4 is a pattern diagram showing a third embodiment of the present invention.

In the figure, a magnetoresistive effect detection conductor 11 and a conductor pattern 12 having a bent tip are arranged with an insulating layer interposed therebetween, and a transfer path 1 formed by ion implantation and the conductor pattern 12 overlap at a cusp 2. When the bubble driven by the in-plane rotating magnetic field 21 reaches the cusp 4, a current is applied to the conductor pattern 12 to expand the bubble. After being detected by the conductor pattern 11, when the current is turned off, the elongated bubbles are attracted to the charged wall generated on the cusp 2, contract to the cusp 2, and are transferred again. As described above, if the present invention is applied, it has the effect of enabling non-destructive reading in a bubble detector that expands a bubble with a pulsed current, detects it, and contracts it again.

Furthermore, the present invention is effective not only for the major lines shown in the embodiments but also for structures combined with arbitrary bubble transfer patterns.

[Brief explanation of the drawing]

FIG. 1 is a pattern diagram showing a conventional bubble detector, and FIGS. 2, 3, and 4 are pattern diagrams showing first, second, and third embodiments of the present invention, respectively. In the figure, 1...bubble transfer path, 2...
... Cusp or gap, 3 and 4 are charged walls, 11 ... Bubble detection conductor pattern, 12 ...
...Conductor pattern, 21...In-plane rotating magnetic field. 2 figures of tusk and 3 figures of gai

Claims (1)

[Claims] 1. A transfer path for transferring magnetic bubbles by an in-plane rotating magnetic field is provided on a magnetic film capable of holding magnetic bubbles, and a first
A magnetic bubble detector in which a conductor and a second conductor are arranged through an insulating layer, a current is applied to the second conductor to enlarge and extend the magnetic bubble, and the presence or absence of a magnetic bubble is detected by the first conductor. A magnetic bubble detector according to the present invention, wherein the second conductor is a hairpin-shaped conductor having a bent portion at its tip, and a portion of the transfer path and the bent portion of the second conductor overlap.